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151.
Phytohormones are involved in the regulation of plant responses to biotic stress. How a limited number of hormones differentially regulate defence responses and influence the outcome of plant–biotic interactions is not fully understood. In recent years, cytokinin (CK) was shown to induce plant resistance against several pathogens. In the present study, we investigated the effect of CK in inducing tomato resistance against the hemibiotrophic pathogenic bacteria Xanthomonas campestris pv. vesicatoria (Xcv) and Pseudomonas syringae pv. tomato (Pst). We demonstrate that CK enhances tomato resistance to Xcv and Pst through a process that relies on salicylic acid and ethylene signalling. CK did not directly affect the growth or biofilm formation ability of these pathogens in vitro. Overall, our work provides insight into the underlying mechanisms of CK-induced immune responses against bacterial pathogens in tomato.  相似文献   
152.
In a pot experiment the soil application of different levels of Cd2+ (0, 10, 20, 30, 40 and 60 µg g–1 soil) affected the lipid components of mustard seeds (Brassica juncea L. Cv. RH-30) markedly. Total lipids declined with the Cd2+ levels regularly while phospho and glycolipids increased only at higher levels. Fatty acids profile of total, neutral and polar lipid fractions were affected considerably. Erucic acid in total and neutral lipids was observed to increase while it decreased in polar lipids with Cd2+ as compared to control. On the other hand palmitic, oleic and linoleic acids had reverse trend. Cadmium concentration increased consistently with increasing levels of Cd2+. Plant dry weight was also decreased significantly with Cd2+ levels.  相似文献   
153.
The present investigation was carried on a 8 parent diallel of mungbean involving 28 F1's and 28 F2's excluding reciprocals grown at three different locations including Meerut, Ludhiana and Hissar. Three different analyses including combining ability, graphical and component analysis were utilized.From the combining ability analysis over different environments it was reported that g.c.a. effects are relatively more consistent over environments than s.c.a. effects. The parents P3 and P5 were ranked as the best general combiners and the cross P5 × P7 was the good specific combination in both the diallel sets. The graphical analysis suggested that high protein content is governed by dominant genes. Further all the analyses revealed that non-additive variance was mostly responsible for this character. Thus two methods, including biparental mating system among the selected F2/F3 plants from P5×P7 cross; and modified diallel selective mating system for the selected parents with good or average general combining ability were suggested. From these populations the desirable combinations with high protein content and other desirable attributes, be selected which can constitute a future variety.  相似文献   
154.
Performance of improved guayule lines in Australia   总被引:1,自引:0,他引:1  
Guayule (Parthenium argentatum Gray) is a potential source of commercial natural rubber. Its commercialisation depends mainly on economical plant production. The objective of this study was to evaluate the performance of improved lines in Australia. Seeds from five improved lines (AZ-1, AZ-2, AZ-3, AZ-5 and AZ-6) and two previously developed guayule lines (N 565 and 11591) were obtained from the Agricultural Research Service (ARS) of the United States Department of Agriculture (USDA). Seedlings from these lines were grown in a glasshouse for 3 months and later transplanted in a field experiment in early September 2001. Plant height and width were monitored from transplanting to 62 weeks at regular intervals. After 62 weeks, plant dry matter production, rubber and resin content, and yields were analysed. Plant height and width of the improved lines were higher than N 565 and 11591. Plant dry matter, rubber and resin yields were significantly different among lines. Of the five lines, AZ-1 and AZ-2 produced rubber yields of 620 and 550 kg/ha, respectively and these yields were significantly greater than for N 565 (371 kg/ha) and 11591 (391 kg/ha). AZ-1 and AZ-2 also produced significantly higher resin yields, 727 and 668 kg/ha, respectively, than those for N 565 (436 kg/ha) and 11591 (325 kg/ha). Rubber and resin yield increase of lines, AZ-1 and AZ-2, were in the range of 41–68% and 53–123%, respectively over N 565 and 11591. AZ-1 tended to produce higher rubber and resin yields than AZ-2 but exhibited highly variable plant height (CV=25%) and width (CV=41%) indicating potential for further genetic improvement. AZ-2 offers the best combination of desirable characters including early vigour, uniformity and comparatively higher rubber and resin yields.  相似文献   
155.
Protein, lysine, tryptophan, crude fibre (CF) and neutral detergent fibre (NDF) of sprouted, normal and hard endosperm opaque-2 (QPM) kernels increased, whereas in vitro protein digestibility (IVPD) decreased substantially up to five days of germination. Following the removal of radicles alone or both radicles and plumules from sprouted kernels, IVPD improved at all the stages of germination. However, the contents of lysine and tryptophan were not affected significantly. For some stages of germination, these amino acids decreased slightly. In sprouted normal kernels, IVPD was higher whereas protein, lysine and tryptophan content was lower than that of sprouted QPM kernels respectively at all the stages of germination. In four days old sprouted normal kernels, after the removal of both radicles and plumules biological value (BV), net protein utilization (NPU) and utilizable protein (UP) increased over non-sprouted kernels whereas true digestibility (TD) reach at par with non-sprouted kernels.  相似文献   
156.
Low cost weaning mixtures were prepared by mixing (i) malted pearl millet (Penicitum typhidium L), roasted amaranth (Amaranthus sp.); roasted green gram (Vigna radiata); jaggery and (ii) malted barley (Dehusked barley); roasted amaranth grain; roasted green gram; jaggery in proportion 60204045 wt/wt and were nutritionally evaluated. Both the blends had a nutrient composition within the range prescribed by the Indian Standard Institute (ISI) for processed weaning foods. The processing of grains resulted in lower levels of phytic acid, polyphenols and saponins and higher in vitro protein digestibility than those of the raw grains used for preparing mixtures. Both the mixtures were acceptable to trained panelists and children.  相似文献   
157.
Chinese chives (Allium tuberosum Rottler ex Sprengel) is a less known cultivated vegetable in western and eastern Himalayan regions of India. This species is reported here for its potential for commercialization to supplement the onion and garlic production in different parts of India especially under the present unpredictable climatic conditions. Due to multipurpose use and wider adaptability of the species future thrust is laid on collection and conservation programmes in India.  相似文献   
158.
Starch has been the most popular and economic size material. Synthetic binders have also been developed to be used as size material to improve weaving loom efficiency. Some synthetic size materials have got restrictions in use mainly because of ecological reasons. In the recent years, many modifications have come up in the starch as a sizing agent. Different modification can give different properties, which can be suited for a particular application. In the present study, for comparative analysis of different varieties of natural starch, modified starch and synthetic size material have been evaluated and mechanical properties like cohesion power, adhesion power, abrasion resistance, bending rigidity etc. were studied. PVA shows best properties among all size material. Among modified starch, starch ester shows better properties.  相似文献   
159.
Soybean (Glycine max (L.) Merrill) is susceptible to the fungal pathogen, Sclerotium rolfsii from seedling emergence to pod fill. A few systemic and non-systemic fungicides have been recommended as pre-sowing seed treatment (ST) for the management of Sclerotium blight of soybean worldwide. But farmers, especially in developing countries do not utilize ST mainly on account of preoccupation in other practices considered by them essential for sowing. The possibility of ST applied well in advance of sowing was therefore investigated. Results indicated that ST on average increased field emergence by 26.19%, reduced post-emergence mortality (POM) by 49.03% and enhanced seed yield by 23.00%. Seed treatment with carboxin 37.5% + thiram 37.5% @ 0.2% was the best. Seed treatment 50 days prior to sowing was superior by increasing emergence, reducing POM and enhancing seed yield with high monetary returns and energy output.  相似文献   
160.
P. Surekha  Rao  B. Mishra    S. R. Gupta    A. Rathore 《Plant Breeding》2008,127(3):256-261
Salinity and alkalinity (sodicity) seriously threaten rice production in south Asia. Improving screening methodologies for identifying sources of tolerance is crucial for breeding salt tolerant rices. Rice genotypes of varying tolerance (tolerant, semi‐tolerant and sensitive) were screened in saline soil of electrical conductivity, ECe 4 and 8 dS/m and alkali soil of pH 9.5 and 9.8 in lysimeters. Vegetative growth events were less affected by both the stresses in comparison to reproductive stage. Grain yield was reduced by 26.7%, 45.7% and 50.3% at ECe 8 dS/m in three tolerance groups respectively. At pH 9.8 the reduction was 25.1%, 37.2% and 67.6% in the three groups respectively. Higher floret fertility contributed to higher seed set and grain yields in tolerant genotypes whereas higher spikelet sterility led to poor seed set and lower grain yields in sensitive genotypes. The 1000 grains weight was also significantly reduced at ECe 4 or pH 9.8. Screening at reproductive stage for morphological traits like floret fertility is thus more useful to identify rice genotypes tolerant to both salinity and alkalinity stress. Genotypic (G) and environmental (E) effects and GE interactions were highly significant for the growth attributes and grain yield. Based on analysis of variance, genotypes tolerant to salinity and alkalinity as well to both the stresses were identified.  相似文献   
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